To my knowledge, there's no "nice" way to go about it. I see most people just screen shotting it, though that doesn't really give you the interactivity you'd want. I think you're mostly stuck using the sites' formatted links for that.
In theory, I guess it would be possible to extract the page and display only the talent calc portion in PHP. I've debated trying to do something like that, but they tend to be very object and graphic heavy and I worry that not only would it make my page load times triple, but the extra processing would lead to my host hanging me by the noose, should I see any smidgen of extra traffic. Maybe that's just me, though.
Vinnie's Web Hosting and Mafia Connections seemed like a good deal at the time.
Which begs the question "how much do I really want to load and display for every reader", but that's a debate all its own. I personally side with a single, simple graphic of the tree and a link to WoWHead. I posted about it a few posts down, but I never shy away from a chance to pimp myself out. The method is on my blog
here. It takes a bit of effort to set up Firefox, but it's a one-time thing.
I am, of course, open to any other methods people are employing.